Our goal is to study the mechanism of traction retinal detachment after the induction of penetrating ocular injury in our experimental animal model. During the course of the study, we have come to understand some of the cellular mechanisms involved. Shortly after injury, myofibroblasts and cells with some ultrastructural characteristics of contractile smooth-muscle cells, in addition to their fibroblast-like characteristics, are apparent. In addition to the ultrastructural evaluation, biochemical investigation of different extracellular factors that may be important in stimulating these cells to contract are under investigation. In addition, in vitro studies of these preparations with specific emphasis on the pharmacologic means of stimulation of contraction are contemplated. Related studies include the investigation of different types of cells and their effects in inducing traction retinal detachment. The injury itself has been evaluated as to the role of penetration with vitreous incarceration in the wound. Blood has been determined to be a very significant stimulus to inflammation and subsequent contraction. Studies of the role of contusion in addition to penetration are also underway. The role of vitrectomy in altering or preventing the sequence of events is a subject of investigation as well.